SYNTHETICAL EESEAECHES ON ACIDS OF THE LACTIC SERIES. 335 



We have likewise prepared the acids corresponding to the three ethers above 

 mentioned. The first is obtained by decomposing ethylic amylhydroxalate with baryta, 

 treating the solution of the barium-salt thus obtained with excess of sulphuric acid, and 

 then dissolving out the organic acid with ether. On evaporating the ethereal solution, 

 the acid remains as a thick oil which does not crystallize after several days' exposure 

 over sulphuric acid in vacuo. The calcium-salt forms a white crystalline mass soluble in 

 water. Submitted to analysis, -2102 grm. gave -0877 grm. calcic sulphate, corresponding 

 to 12 "2 7 per cent, of calcium, the formula 



jCAyHHo 



Ci,H^Ca"Oe,or ,^0 0^^" 



ICAyHHo 

 requiring ]2'12 per cent. 



The barium-salt closely resembles that of calcium. 



•2476 grm. gave on analysis -1334 grm. baric sulphate, corresponding to 31"68 per 



cent, of barium. The formula 



jCAyHHo 



Ci4H26Ba"06,or^^^Ba" 



ICAyHHo 

 requires 32*08 per cent, of barium. . - 



We have also obtained a beautifully crystalline acid of the same composition as 

 the above, from its zinc-salt contained in the residue remaining after the distillation 

 of the three ethers above described. Amy Ihydr oxalic acid prepared from this zinc- 

 salt is but sparingly soluble in water, from which, however, it crystallizes in magnificent 

 nacreous scales that fuse at 60-5° C, but afterwards remain liquid for some time even at 

 ordinary temperatures; they are very imctuous to the touch, and readily soluble in 

 alcohol and ether. On analysis this acid gave the following results : — 



I. "1921 grm. gave -4002 grm, carbonic anhydride and -1702 grm, water. 

 II. "1770 grm. gave '3734 grm, carbonic anhydride and '1556 grm, water. 

 These numbers agree well with those calculated from the formula 



^ „ ^ JCAyHHo 

 C;H,,03,or|^Qjj^ ' 



as the following comparison shows: — 



Calculated, Found. Mean. 



57-25 

 9-80 



146 100-00 



The barium-salt of this acid crystallizes in large and beautiful nacreous scales like 



2z2 



